Boyd J S, Omran S N, Ayliffe T R
Department of Veterinary Anatomy, University of Glasgow Veterinary School.
Vet Rec. 1990 Oct 6;127(14):350-2.
A real time B-mode ultrasound scanner with a 7.5 MHz rectal linear transducer was used in two trials to detect whether dairy cows, less than 25 days after insemination at standing oestrus, were pregnant. In the first trial 17 cows were inseminated on the same day, and their reproductive tracts were examined 14, 15, 16 or 17 days after insemination. All the cows were diagnosed accurately as either pregnant or not pregnant. In the second trial 22 cows were inseminated on the day of observed oestrus while 14 were observed at oestrus but not inseminated. The animals were kept as a mixed group and an experienced operator scanned the uterus of each cow on one occasion, without knowing either the dates of observed oestrus or which cows had been inseminated. The rate of correct diagnosis was only 33 per cent in cows up to 16 days after oestrus, but increased markedly after 17 days and was 100 per cent by day 20.
在两项试验中，使用了一台配备7.5兆赫直肠线性换能器的实时B型超声扫描仪，以检测在发情期站立时输精后不到25天的奶牛是否怀孕。在第一项试验中，17头奶牛在同一天输精，并在输精后14、15、16或17天对其生殖道进行检查。所有奶牛都被准确诊断为怀孕或未怀孕。在第二项试验中，22头奶牛在观察到发情的当天输精，而14头奶牛观察到发情但未输精。这些动物作为一个混合群体饲养，一名经验丰富的操作员在不知道观察到发情的日期或哪些奶牛已经输精的情况下，对每头奶牛的子宫进行了一次扫描。在发情后16天内的奶牛中，正确诊断率仅为33%，但在17天后显著提高，到第20天时达到100%。
